The effect of donor and recipient race on outcomes of assisted reproduction

BACKGROUND

A growing literature suggests that minority races, particularly Black women, have a lower probability of live birth and higher risk of perinatal complications after autologous assisted reproductive technology. However, questions still remain as to whether these racial disparities have arisen because of associations between race and oocyte/embryo quality, the uterine environment, or a combination of the two. Oocyte donation assisted reproductive technology represents a unique approach to examine this question.

OBJECTIVE

This study aimed to evaluate the associations between the race of female oocyte donors and recipients and live birth rates following vitrified donor oocyte assisted reproductive technologies.

STUDY DESIGN

This was a retrospective study conducted at a single, private fertility clinic that included 327 oocyte donors and 899 recipients who underwent 1601 embryo transfer cycles (2008-2015). Self-reported race of the donor and recipient were abstracted from medical records. Live birth was defined as the delivery of at least 1 live-born neonate. We used multivariable cluster weighted generalized estimating equations with binomial distribution and log link function to estimate the adjusted risk ratios of live birth, adjusting for donor age and body mass index, recipient age and body mass index, tubal and uterine factor infertility, and year of oocyte retrieval.

RESULTS

The racial profile of our donors and recipients were similar: 73% white, 13% Black, 4% Hispanic, 8% Asian, and 2% other. Women who received oocytes from Hispanic donors had a significantly higher probability of live birth (adjusted risk ratio, 1.20; 95% confidence interval, 1.05-1.36) than women who received oocytes from white donors. Among Hispanic recipients, however, there was no significant difference in probability of live birth compared with white recipients (adjusted risk ratio, 1.07; 95% confidence interval, 0.90-1.26). Embryo transfer cycles using oocytes from Black donors (adjusted risk ratio, 0.86; 95% confidence interval, 0.72-1.03) and Black recipients (adjusted risk ratio, 0.84; 95% confidence interval, 0.71-0.99) had a lower probability of live birth than white donors and white recipients, respectively. There were no significant differences in the probability of live birth among Hispanic, Asian, and other race recipients compared with white recipients.

CONCLUSION

Black female recipients had a lower probability of live birth following assisted reproductive technology, even when using vitrified oocytes from healthy donors. Female recipients who used vitrified oocytes from Hispanic donors had a higher probability of live birth regardless of their own race.

The effects of oocyte donor and recipient body mass index on live birth rates and pregnancy outcomes following assisted reproduction

Objective

To investigate the effects of oocyte donor and recipient body mass index (BMI) on outcomes of vitrified donor oocyte assisted reproductive technology (ART).

Design

Retrospective cohort study.

Setting

Private fertility center.

Patient(s)

A total of 338 oocyte donors and 932 recipients who underwent 1,651 embryo transfer cycles in 2008–2015.

Intervention(s)

Multivariable log binomial regression models with cluster-weighted generalized estimating equations were used to estimate the adjusted risk ratios.

Main Outcome Measure(s)

Live birth, defined as the delivery of at least one live-born infant, including all embryo transfer cycles. Secondary outcomes included birth weight and gestational length only among singleton live births.

Results

The mean ± SD body mass indexes (BMIs) of donors and recipients were 22.6 ± 2.5 kg/m² and 24.6 ± 4.8 kg/m², respectively. There were no significant associations between donor BMI and probability of live birth. Recipients with BMI ≥35 kg/m² had a significantly higher probability of live birth compared with normal-weight recipients. Among singleton live births, recipients with BMI <18.5 kg/m² had a lower risk whereas women with BMI ≥35 kg/m² had a higher risk of delivery in an earlier gestational week compared with normal weight women. Recipients with a BMI ≥35 kg/m² also had a higher risk of having a low birth weight infant compared with normal-weight women.

Conclusions

In the setting of vitrified donor oocyte ART, recipient BMI was positively associated with probability of live birth but negatively associated with gestational length and birth weight among singleton births.

Effect of oocyte donor stimulation on recipient outcomes: data from a US national donor oocyte bank

STUDY QUESTION

How does ovarian stimulation in an oocyte donor affect the IVF cycle and obstetric outcomes in recipients?

SUMMARY ANSWER

Higher donor oocyte yields may affect the proportion of usable embryos but do not affect live birth delivery rate or obstetric outcomes in oocyte recipients.

WHAT IS KNOWN ALREADY

In autologous oocyte fresh IVF cycles, the highest live birth delivery rates occur when ~15-25 oocytes are retrieved, with a decline thereafter, perhaps due to the hormone milieu, with super-physiologic estrogen levels. There are scant data in donor oocyte cycles, wherein the oocyte environment is separated from the uterine environment.

STUDY DESIGN, SIZE, DURATION

This was a retrospective cohort study from 2008 to 2015 of 350 oocyte donors who underwent a total of 553 ovarian stimulations and oocyte retrievals. The oocytes were vitrified and then distributed to 989 recipients who had 1745 embryo transfers. The primary outcome was live birth delivery rate, defined as the number of deliveries that resulted in at least one live birth per embryo transfer cycle.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study included oocyte donors and recipients at a donor oocyte bank, in collaboration with an academic reproductive endocrinology division. Donors with polycystic ovary syndrome and recipients who used gestational carriers were excluded. The donors all underwent conventional ovarian stimulation using antagonist protocols. None of the embryos underwent pre-implantation genetic testing. The average (mean) number of embryos transferred to recipients was 1.4 (range 1-3).

MAIN RESULTS AND THE ROLE OF CHANCE

Per ovarian stimulation cycle, the median number of oocytes retrieved was 30 (range: 9-95). Among the 1745 embryo transfer cycles, 856 of the cycles resulted in a live birth (49.1%). There were no associations between donor oocyte yield and probability of live birth, adjusting for donor age, BMI, race/ethnicity and retrieval year. The results were similar when analyzing by mature oocytes. Although donors with more oocytes retrieved had a higher number of developed embryos overall, there was a relatively lower percentage of usable embryos per oocyte warmed following fertilization and culture. In our model for the average donor in the data set, holding all variables constant, for each additional five oocytes retrieved, there was a 4% (95% CI 1%, 7%) lower odds of fertilization and 5% (95% CI 2%, 7%) lower odds of having a usable embryo per oocyte warmed. There were no associations between donor oocyte yield and risk of preterm delivery (<37 weeks gestation) and low birthweight (<2500 g) among singleton infants.

LIMITATIONS, REASONS FOR CAUTION

Ovarian stimulation was exclusively performed in oocyte donors. This was a retrospective study design, and we were therefore unable to ensure proportional exposure groups. These findings may not generalizable to older or less healthy women who may be vitrifying oocytes for planned fertility delay. There remain significant risks to aggressive ovarian stimulation, including ovarian hyperstimulation. In addition, long-term health outcomes of extreme ovarian stimulation are lacking. Lastly, we did not collect progesterone levels and are unable to evaluate the impact of rising progesterone on outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Live birth delivery rates remain high with varying amounts of oocytes retrieved in this donor oocyte model. In a vitrified oocyte bank setting, where oocytes are typically sent as a limited number cohort, recipients are not affected by oocyte yields.

STUDY FUNDING/COMPETING INTEREST(S)

Additional REDCap grant support at Emory was provided through UL1 TR000424. Dr. Audrey Gaskins was supported in part by a career development award from the NIEHS (R00ES026648).

Sex selection for non-medical indications: a survey of current pre-implantation genetic screening practices among U.S. ART clinics

PURPOSE

This study aimed to determine the current percentage of United States (U.S.) assisted reproductive technology (ART) clinics offering sex selection via pre-implantation genetic screening (PGS) for non-medical purposes.

METHODS

The authors conducted website review and telephone interview survey of 493 U.S. ART clinics performing in vitro fertilization (IVF) in 2017. Main outcome measures were pre-implantation genetic screening (PGS)/pre-implantation genetic diagnosis (PGD) practices and non-medical sex selection practices including family balancing.

RESULTS

Of the 493 ART clinics in the USA, 482 clinics (97.8%) responded to our telephone interview survey. Among all U.S. ART clinics, 91.9% (n = 449) reported offering PGS and/or PGD. Furthermore, 476 clinics responded to survey questions about sex selection practices. Of those ART clinics, 72.7% (n = 346) reported offering sex selection. More specifically among those clinics offering sex selection, 93.6% (n = 324) reported performing sex selection for family balancing, and 81.2% (n = 281) reported performing for elective purposes (patient preference, regardless of rationale for the request). For couples without infertility, 83.5% (n = 289) of clinics offer sex selection for family balancing and 74.6% (n = 258) for non-specific elective reasons.

CONCLUSIONS

The majority of U.S. ART clinics offer non-medical sex selection, a percentage that has increased substantially since last reported in 2006.